Self-lubricating ammunition



Sept. 28, 1965 J. E. GILES SELF-LUBRICATING AMMUNITION Filed April 4,1963 INVENTOR. JOHN E. Gi LE5 ijea/w RTTORNEYS United States Patent3,208,387 SELF-LUBRICATING AMMUNITION John E. Giles, Rte. 1, Box 41A,Odessa, Fla. Filed Apr. 4, 1963, Ser. No. 270,750 4 Claims. (Cl. 102-92)This invention relates to ammunition for various type weapons and moreparticularly relates to self-lubricating projectiles and method forautomatically lubricating the barrels of such weapons.

Heretofore, various arrangements have been applied for lubricating thebarrel of various type weapons during normal usage thereof. In certainapplications the composition of the metal or alloy constituting thecartridge shell and/or projectile has been varied to include varioustype lubricating ingredients or auxiliary lubricating components, suchas lubricating rings or washers, that have been applied to the cartridgeshell and/ or projectile for purposes of lubrication. Such applicationsnot only have the disadvantages of high cost and complexity ofmanufacture, but incorporate the disadvantage of metal deposition orlead fouling in the barrel of the weapon resulting in poor accuracy anda short end barrel life.

Heretofore, in other applications, lubricants have been applied directlyto the external surfaces of the projectile. Such arrangementsincorporate the disadvantages of the exposed lubricant becomingaccidently dislodged during normal handling of the projectile or incertain applications the lubricant will bleed in hot weather whichproduces severe detrimental effects upon the explosive charge and/ orthe primer of the ammunition.

Therefore, the principal object of the present invention is to provideself-lubricating projectiles and method for automatically lubricatingthe barrel of various type weapons that will increase the accuracy andrange of such ammunition.

Another object of the present invention is to provide self-lubricatingprojectiles of the above type which will substantially increase theaccuracy and range of such ammunition by minimizing the frictionalresistance and lead fouling in the barrel of conventional type weapons.

Another object of the present invention is to provide self-lubricatingprojectiles of the above type which incorporate a heat resistant typelubricant that will effectively lubricate the barrel of a weapon butwhich will not bleed or accumulate excessively in the working parts ofthe weapon, as heretofore the case with conventional wax-typelubricants.

A still further object of the present invention is to provide aself-lubricating projectile of the above type which is simple tomanufacture, inexpensive to produce, and which facilitates reloading ofthe cartridge case by elimination of the wax-type lubricant on theperiphery of the projectile.

Other objects and advantages of the present invention will be apparentfrom the following description taken in conjunction with theaccompanying drawings, wherein:

FIG. 1 is a front elevational view partly in section showing the novelammunition embodying the present invention;

FIG. 2 is a cross-sectional view taken along the plane of line 2-2 ofFIG. 1;

FIG. 3 is a front elevational view partly in section showing a modifiedform of the novel ammunition embodying the present invention;

FIG. 4 is a cross-sectional view taken along the plane of line 4-4 ofFIG. 3;

FIG. 5 is a front elevational view partly in section showing a furthermodified form of the novel ammunition embodying the present invention;

FIG. 6 is a cross-sectional view taken along the plane of line 66 ofFIG. 5; and

Patented Sept. 28, I965 'ice FIG. 7 is a front elevational view partlyin section showing still another modified form of the novel ammunitionembodying the present invention.

In accord with the aforementioned principles and objects, the presentinvention, briefly described, provides a novel self-lubricatingammunition including a projectile adapted for use with a conventionaltype of cartridge shell. In the preferred forms illustrated herein, theprojectile may be provided with reservoirs and/or passages formedtherein and adapted to receive a lubricating media that is adapted to bedistributed onto the interior surfaces of the barrel of a weapon forautomatically lubricating the surfaces of the barrel upon discharge ofthe projectile from the weapon.

In another form, the lubricant may be applied directly to the explosivecharge of the weapon in the form of a lubricant-containing capsule whichis adapted to be disintegrated as part of the explosive charge uponfiring of the weapon.

Referring again to FIGS. 1 and 2 of the drawings, there is illustratedone form of the invention wherein the ammunition designated generally at1 includes a conventional type cartridge shell 2 of a generally tubularshape having a closed rear end and an open front end and which isadapted to receive therein an explosive charge M. The open front end ofthe cartridge shell 2 is of a size sufficient to receive therein thebase 3 of the projectile 4, which may be attached within the open end ofthe cartridge shell 2 by any suitable attachment means, and/ or bysuitable forming operations, such that the projectile may readily bedetached therefrom and propelled axially through the barrel of a weapon(not shown) upon ignition of the explosive charge M.

In accordance with the present invention, the projectile 4 may be madeof any metal or alloy and may be formed to any shape or configuration,as is customary in the art. In the form illustrated, the base 3 of theprojectile 4 may be provided with a concentrically disposed cavity orlubri cant receiving reservoir 5 which extends axially into the body ofthe projectile 4. The reservoir 5 may be of any shape or configurationand of a depth suflicient to accumulate therein an amount of lubricant Lsufiicient to effectively lubricate the internal surfaces of the barrelof a weapon.

In a typical application of this form of the invention, the projectile 4is detached from the cartridge shell 2 and propelled axially through thebarrel of the weapon under the force of the exploding powder gases. Theforce from the explosive charge M presses against the base 3 of theprojectile 4 and spatters or blows the accumulated lubricant L withinthe reservoir 5 generally radially onto the confining interior surfacesof the weapon barrel. The intense heat and pressure from the explodingpowder gases act to vaporize the accumulated lubricant L which readilycirculates around the projectile 4 as it is propelled at a high velocitythrough the barrel, thereby automatically lubricating the interiorsurfaces of the barrel. Moreover, upon discharge of a single round ofsuch self-lubricating ammunition, there is disposed on the interiorsurfaces of the barrel sufficient deposits of lubricant to provide forrepeated firings of conventional type unlubricated ammunition beforefrictional resistance and lead fouling again build up in the barrel tocause any noticeable firing inaccuracy.

In another modified form of the present invention, as shown in FIGS. 3and 4 of the drawings, the base 3 of the projectile 4 may be providedwith a similar concentrically disposed lubricating reservoir 7. In theembodiment illustrated, the projectile 4 is preferably provided with apair of radially extending passages 8 which open at one end into theupper end of the aforementioned reservoir 7. The passages 8 extendupwardly and outwardly from the reservoir 7 and open onto the outerperipheral surface of the projectile 4. The passages 8 may be of anysuitable cross-sectional shape or configuration and of a cross-sectionaldimension sufficient to enable predetermined amounts of lubricant Laccumulated in the reservoir 7 to be exuded therefrom under theinfluence of the explosive charge M.

Moreover, in the modified form of the invention, the force of theexploding powder gases presses against the base 3 of the projectile 4and against the accumulated lubricant L in the reservoir 7, causing thelubricant therein to flow upwardly through the passages 8. The intenseheat and pressure from the explosive charge M causes vaporization of thelubricant which is then exuded from the passages 8 and ahead of theprojectile 4 to automatically lubricate the interior surfaces of thebarrel of the weapon, as aforementioned.

In the forms illustrated in FIGS. 1 to 4 of the drawings, lubricant Lmay readily be deposited within the respective reservoirs and 7 by anysuitable implement or hand tool, such as a hypodermic-grease gun, forexample. Because of the relative viscosity of the lubricant andcapillary action within the reservoirs, the lubricant will beeffectively retained therein during normal usage of the ammunition. Incertain instances, when it is desired to retain the lubricant L separatefrom the explosive charge M, a closure or retaining membrane 6 comprisedof a suitable frangible material, such as paper, waxed paper, or thelike, and which is compatible with the explosive charge, may be providedto close off the opening to the respective lubricant receivingreservoir. In such case, the membrane 6 may readily be attached to thebase 3 of the projectile 4 (FIG. 3) by means of a suitable adhesive,such as paraffin wax or the like.

In another modified form of the present invention illustrated in FIGS. 5and 6 of the drawings, the projectile 4 is shown absent theaforementioned type of lubricant receiving reservoir, but is providedwith an endless circumferentially extending lubricant receiving grooveor slot 9. In the embodiment illustrated, the groove opens onto theexterior surface of the projectile 4 throughout its periphery thereofand extends radially inwardly therefrom a predetermined distance todefine therewith a concentrically disposed axially extending column 10.The radial depth of the groove is preferably less than thecross-sectional thickness of the body of the projectile 4, such that thecolumn 10 constitutes a weakened area or zone of failure which readilydeforms under the pressure from the explosive powder gases, therebyeffectively exuding the lubricant L accumulated within the groove 9 ontothe interior surfaces of the barrel of the weapon.

Moreover, in a typical application of this embodiment of the invention,pressure from the explosive charge presses against the base 3 of theprojectile 4. The material of which the projectile is made beingrelatively soft, such as lead, the column 10 deforms as the projectile 4is discharged axially through the barrel which causes the base 3 to bepressed against the body of the projectile, thereby automaticallyexuding lubricant from the groove 9 onto the interior surface of thebarrel for purposes of lubrication.

In another modified form of the present invention, the lubricant may beapplied directly to the explosive charge M, as best shown in FIG. 7 ofthe drawings. In the embodiment illustrated, it is preferred that thelubricant L be sealed Within an expendable package or capsule 11comprised of a material which is compatible with the explosive charge,such as paper, cellophane, polyethylene, polyvinyl chloride or the like,and which may be readily disintegrated and disposed along with theexploding powder gases, as a part of the charge. Moreover, the capsule11, containing a predetermined amount of lubricant L, may readily bedeposited within the cartridge shell 2 along with the explosive charge Mduring the customary loading or reloading of the ammunition.

In accordance with this modified form of the invention, the force of theexploding powder gases detaches the projectile 4 from the cartridgeshell 2 and propels the projectile axially through the barrel causingthe lubricant containing capsule 11 to disintegrate, thereby effectivelydistributing the lubricant L contained therein against the interiorsurfaces of the barrel, as aforementioned.

In the embodiments illustrated, it is preferred that the lubricatingmedia be comprised of a temperature resistant material, such as asilicone or the like containing grease, which will provide an effectivelubrication of the weapon, which will prevent lead fouling of the barrelafter repeated firings, but which will not form excessive deposits inthe working components of the weapon, as has heretofore been the casewith conventional type ammunition.

From the foregoing description and accompanying drawings, it will beseen that the present invention provides a novel type of selflubricating projectile and method for automatically lubricating thebarrel of various type weapons that effectively increases the accuracyand range of such ammunition by minimizing the resistance caused by leadfouling in the barrel. The present in vention provides aself-lubricating type of projectile which may be easily and economicallymanufactured and/or reloaded and which has a clean and permanent type oflubricant that will not rub off or bleed, as has heretofore been thecase with known types of ammunition.

In addition to such advantages, the present invention provides a noveltype ammunition which incorporates a heat resistant lubricatingmaterial, such as silicone containing grease, which will not build upharmful deposits in the working components of the Weapon therebyresulting in increased accuracy and prolonged life of the weapon.

The terms and expressions which have been used are used as terms ofdescription and not of limitation, and there is no intention in the useof such terms and expressions of excluding any equivalents of any of thefeatures shown or described, or portions thereof, but it is recognizedthat various modifications are possible within the scope of theinvention claimed.

I claim:

1. Self lubricating ammunition comprising in combination, an elongatedcartridge shell having an explosive charge therein, a substantiallysolid projectile having a body including oppositely disposed nose andbase portions, said base portion being cylindrical and said nose portiontapering forwardly from said base portion, said body being detachablyconnected at said base portion to said cartridge shell so as to bepropelled through the barrel of a Weapon upon firing thereof, said baseportion having a flat rear surface extending generally perpendicular tothe axis of said body, said body having a single centrally disposedcavity extending axially from said rear surface into said base portion,said cavity being relatively shallow with respect to the length of saidbase portion, said cavity being completely closed at one end thereof bya concave shaped end wall surface and opening at its other end onto saidrear surface of said base portion, so as to be exposed to the explosivecharge in said cartridge shell, the area of said cavity at said rearsurface being no greater than one-fourth the area of said surface tominimize the effect of said cavity on said explosive charge, and saidcavity being completely filled with a lubricant to be distributedrearwardly therefrom relative to forward movement of said projectile andagainst the interior surfaces of the barrel of said weapon under theexpansive force from said explosive charge.

2. Self lubricating ammunition comprising in combination, an elongatedcartridge shell having an explosive charge contained therein, asubstantially solid projectile having a body including oppositelydisposed nose and base portions, said base portion being cylindrical andsaid nose portion tapering forwardly from said base portion, said bodybeing detachably connected at said base portion to said cartridge shellso as to be propelled through the barrel of a Weapon upon firingthereof, said base portion having a fiat rear surface extendinggenerally perpendicular to the axis of said body, said body having asingle centrally disposed cavity extending axially from said rearsurface into said base portion a distance less than onehalf the lengthof said base portion, said cavity being completely closed at one endthereof by a concave shaped end wall surface and opening at its otherend onto said rear surface of said base portion, the area of said cavityat said rear surface being no greater than one-fourth the area of saidrear surface to minimize the effect of said cavity on said explosivecharge, said cavity being completely filled with a lubricant, anddestructable closure means attached to said base portion and coveringsaid cavity for separating the lubricant therein from said explosivecharge, whereby the firing of said weapon will disintegrate said closuremeans and distribute said lubricant in said cavity rearwardly therefromrelative to forward movement of said projectile and against the interiorsurface of the barrel of said weapon under the expansive force from saidexplosive charge.

3. Self-lubricating ammunition in accordance with claim 1, wherein saidlubricant comprises a heat resistant material, such as silicon grease.

4. Self-lubricating ammunition in accordance with claim 2, wherein saiddestructible closure means includes a frangible membrane comprised ofpaper, which is comparable with the explosive charge, and adhesive meansattaching said membrane to said base portion.

References Cited by the Examiner BENJAMIN A. BORCHELT, Primary Examiner.

1. SELF LUBRICATING AMMUNITION COMPRISING IN COMBINATION, AN ELOGATEDCARTRIDGE SHELL HAVING AN EXPLOSIVE CHARGE THEREIN, A SUBSTANTIALLYSOLID PROJECTILE HAVING A BODY INCLUDING OPPOSITELY DISPOSED NOSE ANDBASE PORTIONS, SAID BASE PORTION BEING CYLINDRICAL AND SAID NOSE PORTIONTAPERING FORWARDLY FROM SAID BASE PORTION, SAID BODY BEING DETACHABLYCONNECTED AT SAID BASE PORTION TO SAID CARTRIDGE SHELL SO AS TO BEPROPELLED THROUGH THE BARREL OF A WEAPON UPON FIRING THEREOFF, SAID BASEPORTION HAVING A FLAT REAR SURFACE EXTENDING GENERALLY PERPENDICULAR TOTHE AXIS OF SAID BODY, SAID BODY HAVING A SINGLE CENTRALLY DISPOSEDCAVITY EXTENDING AXIALLY FROM SAID REAR SURFACE INTO SAID BASE PORTION,SAID CAVITY BEING RELATIVELY SHALLOW WITH RESPECT TO THE LENGTH OF SAIDBASE PORTION, SAID CAVITY BEING COMPLETELY CLOSED AT ONE END THEREOF BYA CONCAVE SHAPED END WALL SURFACE AND OPENING AT ITS OTHER END ONTO SAIDREAR SURFACE OF SAID BASE PORTION, SO AS TO BE EXPOSED TO THE EXPLOSIVECHARGE IN SAID CARTRIDGE SHELL, THE AREA OF SAID CAVITY AT SAID REARSURFACE BEING NO GREATER THAN ONE-FOURTH THE AREA OF SAID SURFACE TOMINIMIZE THE EFFECT OF SAID CAVITY ON SAID EXPLOSIVE CHARGE, AND SAIDCAVITY BEING COMPLETELY FILLED WITH A LUBRICANT TO BE DISTRIBUTEDREARWARDLY THEREFROM RELATIVE TO FORWARD MOVEMENT OF SAID PROJECTILE ANDAGAINST THE INTERIOR SURFACES OF THE BARREL OF SAID WEAPON UNDER THEEXPANSIVE FORCE FROM SAID EXPLOSIVE CHARGE.